CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Activities
Net income	$ 35,542	$ 28,996	$ 26,345
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	1,625	1,500	4,534
Depreciation expense	6,410	5,886	5,783
Amortization of mortgage servicing rights	1,313	1,004	1,472
(Recovery)/additional impairment of valuation allowance on mortgage servicing rights	(200)	25	(750)
Securities amortization, net	3,386	1,973	3,031
Amortization of purchased intangible assets	1,640	1,690	1,868
Earnings on cash surrender value of life insurance policies	(1,236)	(1,298)	(1,378)
Gain on life insurance benefit	(307)
Securities gains, net of impairment	(386)	(24)	(835)
Gain on loans sold	(5,553)	(4,730)	(5,464)
Loans originated for sale	(236,928)	(165,827)	(218,288)
Proceeds from loan sales	243,230	168,832	234,778
Stock based compensation expense	843	647	751
Stock portion of director retainer fee expense	315	359	367
(Gain)/(Loss) on sale and write-down of OREO	(68)	153	539
Prepayment penalty on FHLB advance	2,364		2,239
Change in other assets and liabilities	1,402	4,172	5,091
Net cash provided by operating activities	53,392	43,358	60,083
Investing Activities
Net change in short term investments	(45)	(1,915)
Purchases of securities available for sale	(345,783)	(61,756)	(233,958)
Proceeds from calls, maturities, and payments on securities available for sale	136,799	106,268	125,010
Proceeds from sales of securities available for sale	147,109	27,131	80,151
Loan originations and payments, net	(176,184)	(110,124)	(128,650)
Purchases of premises and equipment	(7,794)	(5,593)	(7,631)
Proceeds from sale of OREO	2,272	3,864	6,023
Purchase of life insurance policies			(504)
Proceeds from redemption of restricted stock	2,785	3,251	10
Purchase of restricted stock	(231)
Proceeds from sale of portfolio loans	11,356
Proceeds from life insurance benefit	1,094	588
Cash received/(paid) for bank/branch acquisitions, net	57,083	(10,686)	18,157
Net cash (used) by investing activities	(171,539)	(48,972)	(141,392)
Financing Activities
Net change in deposits	83,428	83,796	(6,594)
Net change in other borrowings	2,014	(13,293)	4,075
Proceeds from FHLB advances	700,000	825,000	665,000
Repayment of FHLB advances	(647,289)	(874,745)	(560,433)
Cash dividends on preferred stock			(470)
Cash dividends on common stock	(11,680)	(8,726)	(5,709)
Purchase of treasury shares	(3,527)	(319)	(204)
Repurchase of preferred stock			(15,100)
Repayment of subordinated debentures, net		(5,000)	(4,000)
Proceeds from exercise of stock options, including tax benefit	294	66	414
Net cash provided by financing activities	123,240	6,779	76,979
Net change in cash and cash equivalents	5,093	1,165	(4,330)
Cash and cash equivalents, beginning of year	62,485	61,320	65,650
Cash and cash equivalents, end of period	67,578	62,485	61,320
Supplemental cash flow information
Interest paid	8,424	8,807	10,375
Income taxes paid	4,985	4,725	2,400
Supplemental non cash disclosure
Loan balances transferred to foreclosed real estate	1,475	$ 2,585	$ 4,005
Loan balances transferred to loans held for sale	$ 11,356